Ok I know for sure that my sons car has a clog in the exhaust. I pulled the primary o2 sensor and got 25 psi of pressure at 2k rpm. I got the same results at the secondary o2 sensor as well. The car went to zero vacuum at 2k rpm in drive with the vacuum test. When I split the exhaust at the flange for the y pipe the back pressure was gone and the vacuum test shows about 7 inches at 2500 rpm. The motor also pulls pretty hard during the open test where it hit a wall with the exhaust closed. Now I’m left with the single secondary cat and the muffler as the possible clog.
My question now is how can the secondary cat be that clogged while both primary cats ( bank 1 and 2) are fine? What could possibly cause such a backup in the system? Personally I was leaning towards the muffler only because I’ve never seen so much water pour out the exhaust as on this car and I was thinking that maybe the muffler ( original ) was rusted up inside.
Thoughts?
My question now is how can the secondary cat be that clogged while both primary cats ( bank 1 and 2) are fine? What could possibly cause such a backup in the system? Personally I was leaning towards the muffler only because I’ve never seen so much water pour out the exhaust as on this car and I was thinking that maybe the muffler ( original ) was rusted up inside.
Thoughts?